Ignition mechanism of high-voltage power cables under influence of internal heat source

doi:10.16265/j.cnki.issn1003-3033.2024.01.1133

Abstract

Abstract:

In order to explore the spontaneous combustion mechanism of high-voltage power cables under the effect of core heating when it was overloaded or short circuited, heating rods was used to simulate the internal heat source for experimental research. The influence of the power of the internal heat source and the cross-sectional area of the inner core of the cable on the key parameters of the spontaneous combustion characteristics, such as cable temperature rise and ignition time, were analyzed. It was found the whole process of cable from heating to ignition to combustion can be divided into four stages: initial heating, pyrolysis gas escaping, ignition, combustion and extinguishment. The results show that the dripping of insulating layer melt leads to the change of flame shape. The heating rate of the surface temperature of each structural layer of the cable increases with the increase of internal heat source power and the decrease of the distance to the surface of the internal heat source. The increase in the power weakens the influence of the cross-sectional area of the inner core of the cable on the heating rate of each layer. The ignition time of the cable is linearly decreasing with the power of the internal heat source.

Key words: internal heat source, high-voltage power cables, ignition time, cross-sectional area, surface temperature

CLC Number:

X928.7火灾与爆炸事故

WANG Tao, SONG Xiaofeng, XU Wenshu, AN Weiguang. Ignition mechanism of high-voltage power cables under influence of internal heat source[J]. China Safety Science Journal, 2024, 34(1): 200-205.

Figures/Tables 10

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